Class D amplifiers. What's the future look like?

I have a number of amplifiers: Luxman C900U, Bryston 4BSST2, Audio Research VSI 60 Integrated, NAD C298 and some other less noteworthy units. As I swap them in and out of my main system, I've come to the conclusion my very modest NAD C298 is about all I really need. Granted if I had extremely hard to drive speakers, I might be better with the Bryston or Luxman, but driving my Harbeth 40.2 speakers, the NAD is just fine. 

I thought a while ago that class D would quickly overtake amplifier design type mainly due to profit margin which I think would be much greater than A/B and tube. I'm not saying the other design styles would go away, just that D would be the most common style. 

Clearly my prediction is not panning out, at least in the mid and high-end audio world and I'm wondering why? It seems companies such as Bryston, Luxman, McIntosh, Hegel and so many others are sticking by A/B. I'm no "golden ears" guy, but is the perceived sound issue(weather real or imaginary) still holding D back? Maybe my assumption of profit margin is not correct? Maybe the amplifier manufacturers are experimenting with D, but keeping tight lipped until release? Perhaps brand loyalists don't want change similar to what happened with "new coke". What else am I missing?